In a known device of this type (German Offenlegungsschrift No. 3,011,005), the anode housing is arranged essentially horizontally and possesses the electroplating plate on its underside, this plate being provided with a plurality of holes. A major disadvantage of this arrangement is that it requires a comparatively large amount of space in the horizontal direction, and this is a particularly important factor, because several anode housings of this type usually have to be connected in series. Moreover, the case of a horizontal arrangement, it is comparatively difficult, due to the possibility of the metal strip sagging and to non-uniform strip-tensions, to maintain a constant spacing between the electroplating plate and the metal strip. Non-uniform spacings lead, however, to irregular deposits of the coating metal.
It has also been proposed, as initially mentioned, to arrange the anode housing vertically, thus enabling the strip to be moved past the electroplating plate which stands vertically. Since, with this arrangement, the electrolyte issuing from the holes in the electroplating plate quickly flows away downwards, due to the gravitational forces, it remains only momentarily in contact with the surface of the metal strip. Even by this means, it is impossible to produce a metal coating having a uniform thickness and, moreover, the device does not function economically.
The object underlying the invention is to produce a device for electrodepositing a single-sided metal coating onto a metal strip, especially onto a steel strip, of the type initially mentioned, in which device the vertical gap between the electroplating plate and the metal strip which is moved vertically past this plate is completely and uniformly filled, the device thereby making it possible to deposit metal coatings having a constant thickness and, in addition, operating economically.